RayTek FA Thermometer User Manual


 
Installation
MarathonSeriesFA/FR 19
5.4InstallingtheElectronicsHousing
Thedistancebetweentheelectronicshousingandacomputer(viaRS485cable)canbeupto1200m
(4000 feet).This allows ample distance from the harsh environment where the sensinghead is
mountedtoacontrolroomorpulpitwherethecomputerislocated.
Forreliableperformanceitisrecommendedthatthepowersupplybenomorethan
60m(200feet)away!
Followingyoucanseeinstallationexamplesshownwithtwo representativecabletypes.A4wire
cableisusedtowirethe24VDCpowersupplyandoneoutputoftheelectronics
housing.Acoated
12wirecableisusedtowireallinputsandoutputsoftheelectronicshousing.
Sometimesincablebothsetsoftwistedpairwireshavedrainwiresinsidetheirinsulation.These
drainwiresmustbeassembledandconnectedtotheterminallabeledSHIELD(bare).Alsoconnectthe
earth
groundtotheSHIELD(bare)terminal.Thefollowingfigureshowshowtoconfigurethedrain
wiresofboth4‐and12wirecablesbeforeconnectingtothesensorandRS485/RS232converter.
Figure14:ConfiguringtheSensorCable
Thecompletewiringmusthaveonlyonecommonearthgroundpoint!
Cablescanberuntothe electronicsenclosurethroughconduitorfastenedusingtheacompression
fitting.Onceyourunthecableintotheenclosure,attachthecolorcodedbarewirestotheterminals.
Usethe followingfigure(or
diagramonundersideoflid)asawiringguide.Notethattheterminal
blocksintheelectronicsenclosurecanbe“popped”outforeasywireconnections.
Twist braided shield and two drain wires from
the two twisted pairs together
A
ttach to SHIELD
in electronics housing
Earth Ground
Earth Ground
12-wire cable
4-wire cable
To electronics housing
To electronics housing
A
ttach to SHIELD
in electronics housing
e.g.
to power supply,
to RS232/485 converter,
other in
p
uts/out
p
uts
e.g.
to power supply,
0/4 – 20 mA current output